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611.
We propose a methodology, called defender–attacker decision tree analysis, to evaluate defensive actions against terrorist attacks in a dynamic and hostile environment. Like most game‐theoretic formulations of this problem, we assume that the defenders act rationally by maximizing their expected utility or minimizing their expected costs. However, we do not assume that attackers maximize their expected utilities. Instead, we encode the defender's limited knowledge about the attacker's motivations and capabilities as a conditional probability distribution over the attacker's decisions. We apply this methodology to the problem of defending against possible terrorist attacks on commercial airplanes, using one of three weapons: infrared‐guided MANPADS (man‐portable air defense systems), laser‐guided MANPADS, or visually targeted RPGs (rocket propelled grenades). We also evaluate three countermeasures against these weapons: DIRCMs (directional infrared countermeasures), perimeter control around the airport, and hardening airplanes. The model includes deterrence effects, the effectiveness of the countermeasures, and the substitution of weapons and targets once a specific countermeasure is selected. It also includes a second stage of defensive decisions after an attack occurs. Key findings are: (1) due to the high cost of the countermeasures, not implementing countermeasures is the preferred defensive alternative for a large range of parameters; (2) if the probability of an attack and the associated consequences are large, a combination of DIRCMs and ground perimeter control are preferred over any single countermeasure.  相似文献   
612.
613.
Adult mental health clinicians face a range of challenges that hinder their use of family‐focused practices when working with consumers who are parents. The purpose of this study was (a) to examine clinicians' experiences when working with parents and (b) identify strategies they found to be effective when working with parents. Eleven Australian mental health clinicians were recruited who regularly worked with consumers who are parents. Semistructured interviews were conducted within a qualitative paradigm and analysed using interpretative phenomenological analysis. Themes were identified which related to (a) managing sensitive parenting conversations, (b) making decisions about child safety in unclear or unpredictable situations, and (c) working with child protection services. Participants had developed strategies for managing the challenges of the first two practice issues and suggested organizational changes that could facilitate collaboration with child protection services. The findings highlight that the challenges of working with parents with mental health issues cannot be addressed with a one‐size‐fits‐all approach. Initiatives to facilitate the effective support of parents and their children need to be informed by contextual factors, including clinical practice.  相似文献   
614.
This project applies and expands Gallagher’s (2005) theories concerning body image and body schema to the concept of gender in general and in particular how understanding gender through this lens can be used to aid transgender people in understanding their own gender. In addition, the paper discusses the effects of gender-incongruent mirroring for transgender and gender nonconforming persons’ ability to know their own feelings and its role in the development of shame. In furthering the understanding of gender and self-knowledge, the concepts of tacit knowledge and phantom limbs reveal how one comes to know gender as a fundamental aspect of the self.  相似文献   
615.
This study examined the effect of Testofen, a specialised Trigonella foenum-graecum seed extract on the symptoms of possible androgen deficiency, sexual function and serum androgen concentrations in healthy aging males. This was a double-blind, randomised, placebo-controlled trial involving 120 healthy men aged between 43 and 70 years of age. The active treatment was standardised Trigonella foenum-graecum seed extract at a dose of 600?mg/day for 12 weeks. The primary outcome measure was the change in the Aging Male Symptom questionnaire (AMS), a measure of possible androgen deficiency symptoms; secondary outcome measures were sexual function and serum testosterone. There was a significant decrease in AMS score over time and between the active and placebo groups. Sexual function improved, including number of morning erections and frequency of sexual activity. Both total serum testosterone and free testosterone increased compared to placebo after 12 weeks of active treatment. Trigonella foenum-graecum seed extract is a safe and effective treatment for reducing symptoms of possible androgen deficiency, improves sexual function and increases serum testosterone in healthy middle-aged and older men.  相似文献   
616.
This study examined antisocial and prosocial behavior of N = 439 adolescent athletes between 14 and 17 years of age (67 teams). Multi‐level analyses showed that team membership explained 20 and 13 percent of the variance in antisocial and prosocial behavior in the sports context, respectively. The team effects suggest that aggregating antisocial or prosocial adolescents within teams may partially explain differences in antisocial and prosocial behavior among athletes in the sports context. A trend was found toward a relation between higher levels of moral reasoning within teams, and less antisocial behavior in the sports context. Favorable moral atmosphere was positively associated with more prosocial behavior in the sports context. Finally, supportive coach–athlete relationships were associated with both less antisocial and more prosocial behavior in the sports context.  相似文献   
617.
International and national biosecurity policies consider risk assessment a critical component of overall plant health risk analysis. The Agreement on the Application of Sanitary and Phytosanitary Measures, the International Plant Protection Convention, and the Convention on Biological Diversity all provide guidelines and recommendations on how to use risk assessment. This article discusses how these instruments address risk assessment, and makes recommendations on how the risk assessment process needs to incorporate current geospatial predictive science and geographic information systems into the plant health biosecurity risk analysis toolbox.  相似文献   
618.
This study examined the measurement and invariance properties of the R-UCLA and de Jong Gierveld loneliness scales for research involving middle-aged and older adults. Confirmatory factor analyses (CFAs) of data from interviews with adults aged 45–84 revealed limited support for the unidimensionality of either scale while subsequent analyses indicated the multidimensionality of both. However, method effects associated with positive and negative item wording were also evident. Multiple group CFAs provided limited support for assumptions of measurement invariance across age groups and from baseline to follow-up with regard to the R-UCLA scale. In contrast, strong measurement invariance across age groups and successive measurements was established for the bi-dimensional dJG scale. Overall, the findings supported the relative utility of the dJG scale for research involving middle-aged and older adults but suggested a need for attention to the implications of method effects associated with item wording and lack of measurement invariance with respect to item residuals.  相似文献   
619.
The study of deprivation, as a social indicator, is basic in the design and development of public policies because it allows decision makers to identify and analyse needy areas in order to improve their citizens’ well-being. The methodological approach proposed for the development of a new deprivation index is based on the Causal Theory whose conceptual model is analysed using Structural Equations. The domains selected for the deprivation index are: education, employment, income, housing, infrastructures and health. A structural equation model based on variance is the exploratory method used to obtain the indices pertaining to the above mentioned areas; the results obtained are seen to be quite reliable. There is a positive connection between the areas of education, employment and income while the relations between infrastructures and health are found to be negative. The results can be projected at a local level and show basic territorial deficiencies. The spatial units studied are the Andalusian (south of Spain) municipalities (770). The spatial projection of the indices obtained for the domains of deprivation highlights the existence of geographical areas which could be a potential target for public action.  相似文献   
620.
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